diff --git a/src/core/ipv6/ip6.c b/src/core/ipv6/ip6.c
index c381a2f4..20b53dca 100644
--- a/src/core/ipv6/ip6.c
+++ b/src/core/ipv6/ip6.c
@@ -78,7 +78,7 @@
  * @return the netif on which to send to reach dest
  */
 struct netif *
-ip6_route(const struct ip6_addr *src, const struct ip6_addr *dest)
+ip6_route(const ip6_addr_t *src, const ip6_addr_t *dest)
 {
   struct netif *netif;
   s8_t i;
@@ -917,7 +917,7 @@ ip6_output_if_src(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
  *         see ip_output_if() for more return values
  */
 err_t
-ip6_output(struct pbuf *p, ip6_addr_t *src, ip6_addr_t *dest,
+ip6_output(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
           u8_t hl, u8_t tc, u8_t nexth)
 {
   struct netif *netif;
diff --git a/src/include/lwip/ip6.h b/src/include/lwip/ip6.h
index c650dbfe..ccc1bf64 100644
--- a/src/include/lwip/ip6.h
+++ b/src/include/lwip/ip6.h
@@ -162,14 +162,14 @@ PACK_STRUCT_END
 
 
 #define ip6_init() /* TODO should we init current addresses and header pointer? */
-struct netif *ip6_route(const struct ip6_addr *src, const struct ip6_addr *dest);
+struct netif *ip6_route(const ip6_addr_t *src, const ip6_addr_t *dest);
 ip6_addr_t   *ip6_select_source_address(struct netif *netif, const ip6_addr_t * dest);
 err_t         ip6_input(struct pbuf *p, struct netif *inp);
-err_t         ip6_output(struct pbuf *p, struct ip6_addr *src, struct ip6_addr *dest,
+err_t         ip6_output(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
                          u8_t hl, u8_t tc, u8_t nexth);
-err_t         ip6_output_if(struct pbuf *p, const struct ip6_addr *src, const struct ip6_addr *dest,
+err_t         ip6_output_if(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
                             u8_t hl, u8_t tc, u8_t nexth, struct netif *netif);
-err_t         ip6_output_if_src(struct pbuf *p, const struct ip6_addr *src, const struct ip6_addr *dest,
+err_t         ip6_output_if_src(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
                             u8_t hl, u8_t tc, u8_t nexth, struct netif *netif);
 #if LWIP_NETIF_HWADDRHINT
 err_t         ip6_output_hinted(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
diff --git a/src/netif/ppp/pppol2tp.c b/src/netif/ppp/pppol2tp.c
index 0d391c73..742d870c 100644
--- a/src/netif/ppp/pppol2tp.c
+++ b/src/netif/ppp/pppol2tp.c
@@ -82,9 +82,9 @@ static err_t pppol2tp_connect(ppp_pcb *ppp, void *ctx);    /* Be a LAC, connect
 static void pppol2tp_disconnect(ppp_pcb *ppp, void *ctx);  /* Disconnect */
 
  /* Prototypes for procedures local to this file. */
-static void pppol2tp_input_ip4(void *arg, struct udp_pcb *pcb, struct pbuf *p, const struct ip_addr *addr, u16_t port);
+static void pppol2tp_input_ip4(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port);
 #if LWIP_IPV6
-static void pppol2tp_input_ip6(void *arg, struct udp_pcb *pcb, struct pbuf *p, const struct ip6_addr *addr, u16_t port);
+static void pppol2tp_input_ip6(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip6_addr_t *addr, u16_t port);
 #endif /* LWIP_IPV6 */
 static void pppol2tp_input(pppol2tp_pcb *l2tp, struct pbuf *p, u16_t port);
 static void pppol2tp_dispatch_control_packet(pppol2tp_pcb *l2tp, u16_t port, struct pbuf *p, u16_t ns, u16_t nr);
@@ -392,7 +392,7 @@ static void pppol2tp_disconnect(ppp_pcb *ppp, void *ctx) {
 }
 
 /* UDP Callback for incoming IPv4 L2TP frames */
-static void pppol2tp_input_ip4(void *arg, struct udp_pcb *pcb, struct pbuf *p, const struct ip_addr *addr, u16_t port) {
+static void pppol2tp_input_ip4(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port) {
   pppol2tp_pcb *l2tp = (pppol2tp_pcb*)arg;
   LWIP_UNUSED_ARG(pcb);
 
@@ -413,7 +413,7 @@ free_and_return:
 
 #if LWIP_IPV6
 /* UDP Callback for incoming IPv6 L2TP frames */
-static void pppol2tp_input_ip6(void *arg, struct udp_pcb *pcb, struct pbuf *p, const struct ip6_addr *addr, u16_t port) {
+static void pppol2tp_input_ip6(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip6_addr_t *addr, u16_t port) {
   pppol2tp_pcb *l2tp = (pppol2tp_pcb*)arg;
   LWIP_UNUSED_ARG(pcb);